Technological leaps in the electronics industry are often preceded by advances in the art of miniaturization. The desire to pack more information and device features into smaller and smaller spaces has always been a premier driving force in the semiconductor and computer industries. Among the myriad of issues involved in miniaturization is the development of methods for writing very thin lines or electrical circuits onto the surface of a substrate. The questions then become what kind of "pencil" can be used to draw lines which are less than a millionth of a meter wide, and what kind of "paper" do you write on using this "pencil"? For theoretical reasons the "pencil of choice" is light. For a material to then act as the "paper", it must interact with light and undergo some physical change which can then be exploited later on to form the conducting circuitry.
The modern microlithographic process can be illustrated using a positive photoresist material. Microchip circuits are currently formed by applying a thin film of a polymer called a photoresist to the surface of a silicon dioxide coated, silicon wafer. A photoresist is a polymer which is designed to specifically undergo a change in solubility upon exposure to light. The photoresist layer is then masked (selected regions protected from light) to expose only the incipient circuit pattern and photolyzed. The photolyzed regions become more soluble and are selectively washed away to expose the underlying silicon oxide layer while the unexposed regions remain behind. The silicon oxide is then etched to bare the conducting silicon underneath. Finally, the remaining photoresist is stripped away and the result is a wafer possessing conducting circuits etched into its surface. Although successful, this process of drawing electrical circuits is quite protracted and requires numerous processing steps. It would be desirable to design polymeric materials which can be converted directly into conductors upon exposure to light.